user/sven/linux.git/include/linux/buffer_head.h, branch v6.1.152

Merge tag 'mm-stable-2022-10-08' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

2022-10-11T00:53:04Z

Pull MM updates from Andrew Morton: - Yu Zhao's Multi-Gen LRU patches are here. They've been under test in linux-next for a couple of months without, to my knowledge, any negative reports (or any positive ones, come to that). - Also the Maple Tree from Liam Howlett. An overlapping range-based tree for vmas. It it apparently slightly more efficient in its own right, but is mainly targeted at enabling work to reduce mmap_lock contention. Liam has identified a number of other tree users in the kernel which could be beneficially onverted to mapletrees. Yu Zhao has identified a hard-to-hit but "easy to fix" lockdep splat at [1]. This has yet to be addressed due to Liam's unfortunately timed vacation. He is now back and we'll get this fixed up. - Dmitry Vyukov introduces KMSAN: the Kernel Memory Sanitizer. It uses clang-generated instrumentation to detect used-unintialized bugs down to the single bit level. KMSAN keeps finding bugs. New ones, as well as the legacy ones. - Yang Shi adds a userspace mechanism (madvise) to induce a collapse of memory into THPs. - Zach O'Keefe has expanded Yang Shi's madvise(MADV_COLLAPSE) to support file/shmem-backed pages. - userfaultfd updates from Axel Rasmussen - zsmalloc cleanups from Alexey Romanov - cleanups from Miaohe Lin: vmscan, hugetlb_cgroup, hugetlb and memory-failure - Huang Ying adds enhancements to NUMA balancing memory tiering mode's page promotion, with a new way of detecting hot pages. - memcg updates from Shakeel Butt: charging optimizations and reduced memory consumption. - memcg cleanups from Kairui Song. - memcg fixes and cleanups from Johannes Weiner. - Vishal Moola provides more folio conversions - Zhang Yi removed ll_rw_block() :( - migration enhancements from Peter Xu - migration error-path bugfixes from Huang Ying - Aneesh Kumar added ability for a device driver to alter the memory tiering promotion paths. For optimizations by PMEM drivers, DRM drivers, etc. - vma merging improvements from Jakub Matěn. - NUMA hinting cleanups from David Hildenbrand. - xu xin added aditional userspace visibility into KSM merging activity. - THP & KSM code consolidation from Qi Zheng. - more folio work from Matthew Wilcox. - KASAN updates from Andrey Konovalov. - DAMON cleanups from Kaixu Xia. - DAMON work from SeongJae Park: fixes, cleanups. - hugetlb sysfs cleanups from Muchun Song. - Mike Kravetz fixes locking issues in hugetlbfs and in hugetlb core. Link: https://lkml.kernel.org/r/CAOUHufZabH85CeUN-MEMgL8gJGzJEWUrkiM58JkTbBhh-jew0Q@mail.gmail.com [1] * tag 'mm-stable-2022-10-08' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (555 commits) hugetlb: allocate vma lock for all sharable vmas hugetlb: take hugetlb vma_lock when clearing vma_lock->vma pointer hugetlb: fix vma lock handling during split vma and range unmapping mglru: mm/vmscan.c: fix imprecise comments mm/mglru: don't sync disk for each aging cycle mm: memcontrol: drop dead CONFIG_MEMCG_SWAP config symbol mm: memcontrol: use do_memsw_account() in a few more places mm: memcontrol: deprecate swapaccounting=0 mode mm: memcontrol: don't allocate cgroup swap arrays when memcg is disabled mm/secretmem: remove reduntant return value mm/hugetlb: add available_huge_pages() func mm: remove unused inline functions from include/linux/mm_inline.h selftests/vm: add selftest for MADV_COLLAPSE of uffd-minor memory selftests/vm: add file/shmem MADV_COLLAPSE selftest for cleared pmd selftests/vm: add thp collapse shmem testing selftests/vm: add thp collapse file and tmpfs testing selftests/vm: modularize thp collapse memory operations selftests/vm: dedup THP helpers mm/khugepaged: add tracepoint to hpage_collapse_scan_file() mm/madvise: add file and shmem support to MADV_COLLAPSE ...

Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

2022-10-07T00:45:53Z

Pull ext4 updates from Ted Ts'o: "The first two changes involve files outside of fs/ext4: - submit_bh() can never return an error, so change it to return void, and remove the unused checks from its callers - fix I_DIRTY_TIME handling so it will be set even if the inode already has I_DIRTY_INODE Performance: - Always enable i_version counter (as btrfs and xfs already do). Remove some uneeded i_version bumps to avoid unnecessary nfs cache invalidations - Wake up journal waiters in FIFO order, to avoid some journal users from not getting a journal handle for an unfairly long time - In ext4_write_begin() allocate any necessary buffer heads before starting the journal handle - Don't try to prefetch the block allocation bitmaps for a read-only file system Bug Fixes: - Fix a number of fast commit bugs, including resources leaks and out of bound references in various error handling paths and/or if the fast commit log is corrupted - Avoid stopping the online resize early when expanding a file system which is less than 16TiB to a size greater than 16TiB - Fix apparent metadata corruption caused by a race with a metadata buffer head getting migrated while it was trying to be read - Mark the lazy initialization thread freezable to prevent suspend failures - Other miscellaneous bug fixes Cleanups: - Break up the incredibly long ext4_full_super() function by refactoring to move code into more understandable, smaller functions - Remove the deprecated (and ignored) noacl and nouser_attr mount option - Factor out some common code in fast commit handling - Other miscellaneous cleanups" * tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (53 commits) ext4: fix potential out of bound read in ext4_fc_replay_scan() ext4: factor out ext4_fc_get_tl() ext4: introduce EXT4_FC_TAG_BASE_LEN helper ext4: factor out ext4_free_ext_path() ext4: remove unnecessary drop path references in mext_check_coverage() ext4: update 'state->fc_regions_size' after successful memory allocation ext4: fix potential memory leak in ext4_fc_record_regions() ext4: fix potential memory leak in ext4_fc_record_modified_inode() ext4: remove redundant checking in ext4_ioctl_checkpoint jbd2: add miss release buffer head in fc_do_one_pass() ext4: move DIOREAD_NOLOCK setting to ext4_set_def_opts() ext4: remove useless local variable 'blocksize' ext4: unify the ext4 super block loading operation ext4: factor out ext4_journal_data_mode_check() ext4: factor out ext4_load_and_init_journal() ext4: factor out ext4_group_desc_init() and ext4_group_desc_free() ext4: factor out ext4_geometry_check() ext4: factor out ext4_check_feature_compatibility() ext4: factor out ext4_init_metadata_csum() ext4: factor out ext4_encoding_init() ...

fs/buffer: make submit_bh & submit_bh_wbc return type as void

2022-09-30T03:01:40Z

submit_bh/submit_bh_wbc are non-blocking functions which just submit the bio and return. The caller of submit_bh/submit_bh_wbc needs to wait on buffer till I/O completion and then check buffer head's b_state field to know if there was any I/O error. Hence there is no need for these functions to have any return type. Even now they always returns 0. Hence drop the return value and make their return type as void to avoid any confusion. Reviewed-by: Christoph Hellwig Reviewed-by: Jan Kara Signed-off-by: Ritesh Harjani (IBM) Link: https://lore.kernel.org/r/cb66ef823374cdd94d2d03083ce13de844fffd41.1660788334.git.ritesh.list@gmail.com Signed-off-by: Theodore Ts'o

fs/buffer: remove bh_submit_read() helper

2022-09-12T03:26:08Z

bh_submit_read() has no user anymore, just remove it. Link: https://lkml.kernel.org/r/20220901133505.2510834-15-yi.zhang@huawei.com Signed-off-by: Zhang Yi Reviewed-by: Jan Kara Reviewed-by: Christoph Hellwig Signed-off-by: Andrew Morton

fs/buffer: remove ll_rw_block() helper

2022-09-12T03:26:08Z

Now that all ll_rw_block() users has been replaced to new safe helpers, we just remove it here. Link: https://lkml.kernel.org/r/20220901133505.2510834-13-yi.zhang@huawei.com Signed-off-by: Zhang Yi Reviewed-by: Jan Kara Reviewed-by: Christoph Hellwig Signed-off-by: Andrew Morton

fs/buffer: add some new buffer read helpers

2022-09-12T03:26:06Z

Current ll_rw_block() helper is fragile because it assumes that locked buffer means it's under IO which is submitted by some other who holds the lock, it skip buffer if it failed to get the lock, so it's only safe on the readahead path. Unfortunately, now that most filesystems still use this helper mistakenly on the sync metadata read path. There is no guarantee that the one who holds the buffer lock always submit IO (e.g. buffer_migrate_folio_norefs() after commit 88dbcbb3a484 ("blkdev: avoid migration stalls for blkdev pages"), it could lead to false positive -EIO when submitting reading IO. This patch add some friendly buffer read helpers to prepare replacing ll_rw_block() and similar calls. We can only call bh_readahead_[] helpers for the readahead paths. Link: https://lkml.kernel.org/r/20220901133505.2510834-3-yi.zhang@huawei.com Signed-off-by: Zhang Yi Reviewed-by: Jan Kara Reviewed-by: Christoph Hellwig Signed-off-by: Andrew Morton

fs/buffer: remove __breadahead_gfp()

2022-09-12T03:26:06Z

Patch series "fs/buffer: remove ll_rw_block()", v2. ll_rw_block() will skip locked buffer before submitting IO, it assumes that locked buffer means it is under IO. This assumption is not always true because we cannot guarantee every buffer lock path would submit IO. After commit 88dbcbb3a484 ("blkdev: avoid migration stalls for blkdev pages"), buffer_migrate_folio_norefs() becomes one exceptional case, and there may be others. So ll_rw_block() is not safe on the sync read path, we could get false positive EIO return value when filesystem reading metadata. It seems that it could be only used on the readahead path. Unfortunately, many filesystem misuse the ll_rw_block() on the sync read path. This patch set just remove ll_rw_block() and add new friendly helpers, which could prevent false positive EIO on the read metadata path. Thanks for the suggestion from Jan, the original discussion is at [1]. patch 1: remove unused helpers in fs/buffer.c patch 2: add new bh_read_[*] helpers patch 3-11: remove all ll_rw_block() calls in filesystems patch 12-14: do some leftover cleanups. [1]. https://lore.kernel.org/linux-mm/20220825080146.2021641-1-chengzhihao1@huawei.com/ This patch (of 14): No one use __breadahead_gfp() and sb_breadahead_unmovable() any more, remove them. Link: https://lkml.kernel.org/r/20220901133505.2510834-1-yi.zhang@huawei.com Link: https://lkml.kernel.org/r/20220901133505.2510834-2-yi.zhang@huawei.com Signed-off-by: Zhang Yi Reviewed-by: Jan Kara Reviewed-by: Christoph Hellwig Cc: Alexander Viro Cc: Andreas Gruenbacher Cc: Bob Peterson Cc: Evgeniy Dushistov Cc: Heming Zhao Cc: Jens Axboe Cc: Konstantin Komarov Cc: Mark Fasheh Cc: Theodore Ts'o Cc: Yu Kuai Cc: Zhihao Cheng Signed-off-by: Andrew Morton

fs: only do a memory barrier for the first set_buffer_uptodate()

2022-09-08T11:58:46Z

Commit d4252071b97d ("add barriers to buffer_uptodate and set_buffer_uptodate") added proper memory barriers to the buffer head BH_Uptodate bit, so that anybody who tests a buffer for being up-to-date will be guaranteed to actually see initialized state. However, that commit didn't _just_ add the memory barrier, it also ended up dropping the "was it already set" logic that the BUFFER_FNS() macro had. That's conceptually the right thing for a generic "this is a memory barrier" operation, but in the case of the buffer contents, we really only care about the memory barrier for the _first_ time we set the bit, in that the only memory ordering protection we need is to avoid anybody seeing uninitialized memory contents. Any other access ordering wouldn't be about the BH_Uptodate bit anyway, and would require some other proper lock (typically BH_Lock or the folio lock). A reader that races with somebody invalidating the buffer head isn't an issue wrt the memory ordering, it's a serialization issue. Now, you'd think that the buffer head operations don't matter in this day and age (and I certainly thought so), but apparently some loads still end up being heavy users of buffer heads. In particular, the kernel test robot reported that not having this bit access optimization in place caused a noticeable direct IO performance regression on ext4: fxmark.ssd_ext4_no_jnl_DWTL_54_directio.works/sec -26.5% regression although you presumably need a fast disk and a lot of cores to actually notice. Link: https://lore.kernel.org/all/Yw8L7HTZ%2FdE2%2Fo9C@xsang-OptiPlex-9020/ Reported-by: kernel test robot Tested-by: Fengwei Yin Cc: Mikulas Patocka Cc: Matthew Wilcox (Oracle) Cc: stable@kernel.org Signed-off-by: Linus Torvalds

wait_on_bit: add an acquire memory barrier

2022-08-26T16:30:25Z

There are several places in the kernel where wait_on_bit is not followed by a memory barrier (for example, in drivers/md/dm-bufio.c:new_read). On architectures with weak memory ordering, it may happen that memory accesses that follow wait_on_bit are reordered before wait_on_bit and they may return invalid data. Fix this class of bugs by introducing a new function "test_bit_acquire" that works like test_bit, but has acquire memory ordering semantics. Signed-off-by: Mikulas Patocka Acked-by: Will Deacon Cc: stable@vger.kernel.org Signed-off-by: Linus Torvalds

add barriers to buffer_uptodate and set_buffer_uptodate

2022-08-09T22:03:02Z

Let's have a look at this piece of code in __bread_slow: get_bh(bh); bh->b_end_io = end_buffer_read_sync; submit_bh(REQ_OP_READ, 0, bh); wait_on_buffer(bh); if (buffer_uptodate(bh)) return bh; Neither wait_on_buffer nor buffer_uptodate contain any memory barrier. Consequently, if someone calls sb_bread and then reads the buffer data, the read of buffer data may be executed before wait_on_buffer(bh) on architectures with weak memory ordering and it may return invalid data. Fix this bug by adding a memory barrier to set_buffer_uptodate and an acquire barrier to buffer_uptodate (in a similar way as folio_test_uptodate and folio_mark_uptodate). Signed-off-by: Mikulas Patocka Reviewed-by: Matthew Wilcox (Oracle) Cc: stable@vger.kernel.org Signed-off-by: Linus Torvalds